<h4>Tool</h4><table border="0"><tr><td valign="top"><b>Name</b></td><td valign="top">Convex Hull</td></tr><tr><td valign="top"><b>ID</b></td><td valign="top">12</td></tr><tr><td valign="top"><b>Author</b></td><td valign="top">O.Conrad (c) 2011</td></tr></table><hr><h4>Description</h4>Implementation of 'Andrew's Monotone Chain Algorithm' for convex hull construction. 
References:
Algorithmist (2011): <a target="_blank" href="http://www.algorithmist.com/index.php/Monotone_Chain_Convex_Hull.cpp">Monotone Chain Convex Hull</a>. algorithmist.com.
Andrew, A.M. (1979): Another Efficient Algorithm for Convex Hulls in Two Dimensions. Info. Proc. Letters 9, pp.216-219.
Sunday, D. (2001-2006): <a target="_blank" href="http://www.softsurfer.com/Archive/algorithm_0109">The Convex Hull of a 2D Point Set or Polygon</a>. Softsurfer.com.
<hr><h4>Parameters</h4><table border="1" width="100%" valign="top" cellpadding="5" rules="all"><tr><th>Name</th><th>Type</th><th>Identifier</th><th>Description</th><th>Constraints</th></tr>
<tr><th colspan="5">Input</th></tr><tr><td>Points </td><td>Shapes (input)</td><td>SHAPES</td><td></td><td></td></tr><tr><th colspan="5">Output</th></tr><tr><td>Convex Hull</td><td>Shapes (output)</td><td>HULLS</td><td></td><td></td></tr><tr><td>Minimum Bounding Box (*)</td><td>Shapes (optional output)</td><td>BOXES</td><td></td><td></td></tr><tr><th colspan="5">Options</th></tr><tr><td>Hull Construction</td><td>Choice</td><td>POLYPOINTS</td><td>This option does not apply to simple point layers.</td><td>Available Choices:
[0] one hull for all shapes
[1] one hull per shape
[2] one hull per shape part
Default: 1</td></tr></table>(*) <i>optional</i>